Abrasive belt machine



27, 1947. T ETAL 2,421,2 9

ABRASIVE BELT MACHINE I Filed Dec. 27, 1944 INVENTOR. LOUiS ROTH JOHNMScHNAus A TTORNEY.

Patented May 27, 1947 UNITED STATES PATENT OFFICE Louis Roth, Du Bois,and John M. Schnaus, Jasper, Ind.

Application December 27, 1944, Serial No. 570.490

5 Claims. 1

Our invention relates to abrasive machines.

It is a main object of our invention to provide in an abrasive machineemploying. an abrasive band traveling at high speed a spring suspendedsand belt forming block for forcing the belt into contact with the edgeface of wood or similar material after it has been operated upon by anedge tool or tools whereby it is expeditiously smoothed and brought toshape and/ or size and has special reference to effecting the finalfinish on curved, irregular or molded edge faces of material.

Another main object of this invention resides in providing africtionless-mounting for the sanding block referred to in the precedingparagraph.

Another object of this invention resides in providing a mounting forasanding. block wherein the latter will remain in balance at all times,that is, Whether idle or at work and subjected to pressures ranging fromlight to heavy work thereby simulating the action of a human hand underthe guidance. of a highly trained skilled operator.

Still another object of this invention resides in providing asuspension. for a sanding block of the type specified above wherein the.weight of said block is yieldingly suspended. at all times therebypreventing the weight of the block. from resting on the stock undertreatment.

Other objects and advantages will. be manifest as the description ofthis invention progresses.

In the accompanying drawings selected for disclosing an embodiment ofour invention:

Figure 1 is a perspective view of our sanding block and the mountingtherefor reproduced from a photograph of a full size device that hasbeen in use finishing edge faces and moldings for commerce. Thestructure shown in this figure is designated as and. referred tohereinafter sometimes as unit'A.

Figure 2; is a front end elevation of Figure 1.

Figure3 is a planview showing a typicalabrading machine equipped withour'improved sanding unit ona reduced scale from that employed inFigures 1. and 2.

Figure .4 is a vertical section elevation of Figure 3; along line 4, 4without the sanding belt,.auxiliary idler therefor or the elements inthe background thereof.

Numeral 5 designates a sanding block that is pivotally mounted on arm 6depending from flat spring 1 by means of pivot shaft 8 journaled in theblock. The arm is shown astride and preferably riveted to the springadjacent the free end 1A thereof. Obviously, a pivot mounting can besubstituted for the rivet attachment. The lower from any convenientsource. spindle t8 carries a large horizontal pulley or ends ofauxiliary aligning springs 9-9 are attached to block 5 and the upperends to bolts 19, H) that pass through spring I freely and carry wingnuts H, H. The lower end 13 of spring I is provided with slot 1C thatregisters with slot 12A in. base plate l2 in order that bolt 13 can assthrough yoke IA and said slots when the complete sanding unit A is to beattached to the top of the abrasive machine shown in Figures 3' and 4.-The function of bolts It, It: and the wing nuts USA at the top endthereof is to set the free end of the flat spring in terms of baseplatel2 to which the lower ends of said bolts are anchored as best shownin Figure 1. It will be observed that free end 1A of the. flat springand arm 6 depending therefrom will be raised or lowered in response tocorresponding manipulation of wing nuts HS'Av thereby raising orlowering block 5, through micrometer adjustments, an important featurethat contributes to the main objectives of the structure constitutingunit A. It will be pointed. out more in detail hereafter as to theutility of raising and lowering the face 5A of block 5.

Numeral l1 designates a frame or'table having at one end a verticalspindle I8, supported in suitable bearings and rotated by belt i9,running on pulley 20 from drive pulley 2|, which in turn ismoun-ted onhorizontal shaft 2 2-, driven by power The upper end of drum 23 fixedthereon, and at the opposite end of the table is a similar pulley 2Gmounted on short shaft25 so as to revolve freely thereon.

Numeral 26 designates anendless belt or'band of webbing coated on theouter face with an abrasive of the desired-fineness embedded in glue,according to'well understood practice. The band should be of a lengthsuflici'ent to form a belt running snugly upon pulleys Z3 and: 24, andin order to take up any slack resulting from the usual causes, the shortshaft 25 is preferably mounted on: slide 28, carried: in ways 29 on thetable and adjusted longitudinally of the latter by screw 30. Numerals21, 2! indicate conventional idlersor guide members. for directing the.band from the. normal. line extending from: drum 2'3, face 5A and drum24. For processing certain objects, such as irregular edge faces oftable tops or the like, the belt must be directed from said normal lineto prevent contact between same at points other than at face 5A.

At about the mid-length of the table top l5 and within the band, unit Ais mounted so that face 5A of sanding block 5 will be in alignmentrangement working face A of block 5 and/or said block can be equallydisposed on each vertical side thereof. Obviously, this feature con--tributes to the balancing of pressures adverted 4 said table forentirely suspending said block, said block having a face conforming tothe edge face to be finished; a sanding belt operatively associated withsaid block; means for driving said belt, the belt being trained over theface of said block, means for adjusting said spring and a pair ofauxiliary springs attached to said main spring and said block forbalancing the block and locating the face thereof.

3. In apparatus for sanding edge faces or the like comprising a table, amain spring mounted on said table, a sanding block mounted on said to atthe outset hereof. It should also be noted in Figure 3 that even ifidlers 21, 2'! were omitted the near section of said belt 26 would beforced out of a vertical plane or straight travel from the near faces ofpulleys 23-24 by face 5A so that said belt will be strained outwardlywhen an edge face or molding is pressed against the area of the sandbelt traveling rapidly over face 5A said belt will be forced to conformto the abutting exterior, thereby effecting a final finish, in a singleoperation, of the applied edge face or molding.

Numeral 3| is a folding leaf mounted in frame 32 supported in verticalways 33 on the main frame I1 and adjustable vertically by screw 3'1 andhand wheel 36 keyed thereto according to accepted practice. Leaf 31 isso set for working that its upper edge projects above the edge of tabletop l5 in front of face 5A and functions as a convenient support for thearticles under treatment. This leaf 3| is hinged to the frame at the topand the angle of said leaf -31 may be varied as required by releasingscrew 35 impinging against the side of segmental arm 38, as indicated inthe drawings and elevating or lowering the free end of the leaf untilthe desired inclination of the top face thereof is attained after whichscrew 3 5 is tightened.

By the means set forth above, it will be understood that the objectsadverted to at the outset of this specification can be accomplishedeasily, expeditiously and uniformly. It will also be understood thatmodifications can be made without departing from the spirit of thisinvention, consequently we' Wish to be limited only by the claimsappearing herein.

We claim:

1. In apparatus for sanding edge faces or the like comprising a table, aleaf spring of substantially 0 formation having one end secured to thetop of said table, a sanding block suspended from the free end of saidspring by a rigid arm pivotally attached to said block for freemovement, said block having a face conforming to the edge faces'to befinished and a sanding belt disposed so that the edges thereof will besubstantially parallel to the top of said table; means for driving saidbelt, the belt being trained'over the face of said block.

2. In apparatus for sanding edge faces or the like comprising a table, asanding block, a main spring means operatively mounted in relation tospring, auxiliary spring means connected at one end to the main springand at the other end to the block, said block having a face conforminggo the edge faces to be finished; a sanding belt di posed so that theedges thereof will be substanttially parallel to the top of said table;means for driving said belt, the belt being trained over the face ofsaid block, said block being suspended entirely from said main springand balanced by said auxiliary springs, each of said springs beingprovided with individual means for varying respectively the tensionthereof.

4. In an apparatus for sanding the edge faces of boards or the likecomprising a table, a leaf spring, said spring having one end secured tothe top of said table, an arm depending from the free end of saidspring, a sanding block having a face for engagement with an abrasivemedium, said sanding block being oscillatively suspended from the freeend of said spring with an axis of said block retained in spaced-fixedrelation to said free end, and yielding means cooperating with said freeend and said block to provide free movement thereof in response to forceapplied thereto through the abrasive medium to said face.

5. In apparatus for sanding edge faces or the like comprising a table, amain spring mounted on said table, a sanding block mounted on saidspring, auxiliary spring means connected at one end to the main springand at the other end to the block, said block having a face conformingto the edge faces to be finished; a sanding belt disposed so that theedges thereof will be substantially parallel to the top of said table;means for driving said belt, the belt being trained over the face ofsaid block, said block being suspended entirely from said main springand balanced by said auxiliary springs.

LOUIS ROTH. JOHN M. SCHNAUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Breed July 18, 1939

